InertialFusionRelated Hydrodynamic Instabilities in a Spherical Gas Bubble Accelerated by a Planar Shock Wave
Abstract
Experiments studying the compression and unstable growth of a dense spherical bubble in a gaseous medium subjected to a strong planar shock wave (2.8 < M < 3.4) are performed in a vertical shock tube. The test gas is initially contained in a freefalling spherical soapfilm bubble, and the shocked bubble is imaged using planar laser diagnostics. Concurrently, simulations are carried out using a compressible hydrodynamics code in rz axisymmetric geometry.Experiments and computations indicate the formation of characteristic vortical structures in the postshock flow, due to RichtmyerMeshkov and KelvinHelmholtz instabilities, and smallerscale vortices due to secondary effects. Inconsistencies between experimental and computational results are examined, and the usefulness of the current axisymmetric approach is evaluated.
 Authors:
 University of WisconsinMadison (United States)
 Lawrence Livermore National Laboratory (United States)
 Publication Date:
 OSTI Identifier:
 20854065
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Fusion Science and Technology; Journal Volume: 47; Journal Issue: 4; Other Information: Copyright (c) 2006 American Nuclear Society (ANS), United States, All rights reserved. http://epubs.ans.org/; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; AXIAL SYMMETRY; BUBBLES; COMPUTERIZED SIMULATION; GEOMETRY; HELMHOLTZ INSTABILITY; HYDRODYNAMICS; ICF DEVICES; INERTIAL CONFINEMENT; INERTIAL FUSION DRIVERS; LASERS; PLASMA SIMULATION; SHOCK TUBES; SHOCK WAVES; SPHERICAL CONFIGURATION; VORTICES
Citation Formats
Niederhaus, John, Ranjan, Devesh, Anderson, Mark, Oakley, Jason, Bonazza, Riccardo, and Greenough, Jeff. InertialFusionRelated Hydrodynamic Instabilities in a Spherical Gas Bubble Accelerated by a Planar Shock Wave. United States: N. p., 2005.
Web.
Niederhaus, John, Ranjan, Devesh, Anderson, Mark, Oakley, Jason, Bonazza, Riccardo, & Greenough, Jeff. InertialFusionRelated Hydrodynamic Instabilities in a Spherical Gas Bubble Accelerated by a Planar Shock Wave. United States.
Niederhaus, John, Ranjan, Devesh, Anderson, Mark, Oakley, Jason, Bonazza, Riccardo, and Greenough, Jeff. 2005.
"InertialFusionRelated Hydrodynamic Instabilities in a Spherical Gas Bubble Accelerated by a Planar Shock Wave". United States.
doi:.
@article{osti_20854065,
title = {InertialFusionRelated Hydrodynamic Instabilities in a Spherical Gas Bubble Accelerated by a Planar Shock Wave},
author = {Niederhaus, John and Ranjan, Devesh and Anderson, Mark and Oakley, Jason and Bonazza, Riccardo and Greenough, Jeff},
abstractNote = {Experiments studying the compression and unstable growth of a dense spherical bubble in a gaseous medium subjected to a strong planar shock wave (2.8 < M < 3.4) are performed in a vertical shock tube. The test gas is initially contained in a freefalling spherical soapfilm bubble, and the shocked bubble is imaged using planar laser diagnostics. Concurrently, simulations are carried out using a compressible hydrodynamics code in rz axisymmetric geometry.Experiments and computations indicate the formation of characteristic vortical structures in the postshock flow, due to RichtmyerMeshkov and KelvinHelmholtz instabilities, and smallerscale vortices due to secondary effects. Inconsistencies between experimental and computational results are examined, and the usefulness of the current axisymmetric approach is evaluated.},
doi = {},
journal = {Fusion Science and Technology},
number = 4,
volume = 47,
place = {United States},
year = 2005,
month = 5
}

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